Hakuoki ~Demon of the Fleeting Blossom~

Chizuru Yukimura, a young woman from a doctor's family, sets out to find her missing father Koudou in 1864 Japan. Disguising herself as a man, she travels to Kyoto, where she encounters ronin being killed by white-haired men. The Shinsengumi arrive and take her in, initially intending to harm her. However, once she reveals her father's name, they decide to protect her due to their own search for Koudou, who has a significant connection to the Shinsengumi.